1. Field
The present invention relates to an information processing apparatus, and more particularly to an information processing apparatus that simultaneously outputs single video/image information to a plurality of display devices.
2. Description of the Related Art
Various notebook personal computers and laptop computers have recently been developed. The personal computer is equipped with a flat-panel display, such as a Liquid-crystal Display (LCD), as an internal display device. The personal computer is equipped with a connector to which an external display device having a Cathode-ray Tube (CRT) or an LCD is connected as necessary, and video/image information, such as a motion picture, is output to the thus-connected external display device as to an internal display device.
In order to display appropriate video/image information on the external display device, the personal computer acquires Extended Display Identification Data (EDID) information from the external display device. The EDID information includes information about the type of a signal that the external display device can process, information about the resolution of a display, and information such as a horizontal effective period and a vertical effective period.
An image output device, such as a personal computer, capable of appropriately setting display conditions for an external display device when connected to the external display device has hitherto been disclosed (see JP-A-2005-109703, for instance). The image output device can convert image information to most appropriate image information by reference to EDID information and output the thus-converted information to the connected external display device.
Some of information processing apparatus, such as personal computers, have internal display devices and a clone display function of simultaneously outputting video/image information identical with video/image information displayed on the internal display device to an external display device connected to the information processing apparatus by a connector.
Of the display devices, some display devices are configured in such a way that an aspect ratio assumes; for example, a ratio of 16:10 or a ratio of 4:3. In such a case, video/image information to be originally displayed in the same manner on both the internal display device and the external display device cannot be displayed appropriately. For instance, when the internal display device has an aspect ratio of 4:3 and the external display device has an aspect ratio of 16:10, video/image information having an appropriate dot aspect ratio of 1:1 is displayed on the internal display device. However, since the external display device is affected by the aspect ratio of the internal display device, a vertically-oriented image whose dot aspect ratio is laterally extended 1.2 times to a ratio of 1.2:1 is displayed on the external display device.
The related-art image output device described in JP-A-2005-109703 can optimally convert image information to be output to a single external display device and can output the thus-converted image information. However, an image output device that provides an optimum clone of a display on both the internal display device and the external display device has not been described.